package com.inforich.common.utils;

import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import javax.crypto.Cipher;
import org.apache.commons.codec.binary.Base64;

/**
 * RSA加密解密
 *
 * @author ruoyi
 **/
public class RsaUtils {

  public static String publicKey = "MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBAKoR8mX0rGKLqzcWmOzbfj64K8ZIgOdHnzkXSOVOZbFu/TJhZ7rFAN+eaGkl3C4buccQd/EjEsj9ir7ijT7h96MCAwEAAQ==";
  // Rsa 私钥
  public static String privateKey =
      "MIIBVAIBADANBgkqhkiG9w0BAQEFAASCAT4wggE6AgEAAkEAqhHyZfSsYourNxaY"
          + "7Nt+PrgrxkiA50efORdI5U5lsW79MmFnusUA355oaSXcLhu5xxB38SMSyP2KvuKN"
          + "PuH3owIDAQABAkAfoiLyL+Z4lf4Myxk6xUDgLaWGximj20CUf+5BKKnlrK+Ed8gA"
          + "kM0HqoTt2UZwA5E2MzS4EI2gjfQhz5X28uqxAiEA3wNFxfrCZlSZHb0gn2zDpWow"
          + "cSxQAgiCstxGUoOqlW8CIQDDOerGKH5OmCJ4Z21v+F25WaHYPxCFMvwxpcw99Ecv"
          + "DQIgIdhDTIqD2jfYjPTY8Jj3EDGPbH2HHuffvflECt3Ek60CIQCFRlCkHpi7hthh"
          + "YhovyloRYsM+IS9h/0BzlEAuO0ktMQIgSPT3aFAgJYwKpqRYKlLDVcflZFCKY7u3"
          + "UP8iWi1Qw0Y=";

  /**
   * 私钥解密
   *
   * @param text 待解密的文本
   * @return 解密后的文本
   */
  public static String decryptByPrivateKey(String text) {
    try {
      return decryptByPrivateKey(privateKey, text);
    } catch (Exception e) {
      return "";
    }
  }

  /**
   * 公钥解密
   *
   * @param publicKeyString 公钥
   * @param text            待解密的信息
   * @return 解密后的文本
   */
  public static String decryptByPublicKey(String publicKeyString, String text) throws Exception {
    X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(
        Base64.decodeBase64(publicKeyString));
    KeyFactory keyFactory = KeyFactory.getInstance("RSA");
    PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
    Cipher cipher = Cipher.getInstance("RSA");
    cipher.init(Cipher.DECRYPT_MODE, publicKey);
    byte[] result = cipher.doFinal(Base64.decodeBase64(text));
    return new String(result);
  }

  /**
   * 私钥加密
   *
   * @param privateKeyString 私钥
   * @param text             待加密的信息
   * @return 加密后的文本
   */
  public static String encryptByPrivateKey(String privateKeyString, String text) throws Exception {
    PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(
        Base64.decodeBase64(privateKeyString));
    KeyFactory keyFactory = KeyFactory.getInstance("RSA");
    PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
    Cipher cipher = Cipher.getInstance("RSA");
    cipher.init(Cipher.ENCRYPT_MODE, privateKey);
    byte[] result = cipher.doFinal(text.getBytes());
    return Base64.encodeBase64String(result);
  }

  /**
   * 私钥解密
   *
   * @param privateKeyString 私钥
   * @param text             待解密的文本
   * @return 解密后的文本
   */
  public static String decryptByPrivateKey(String privateKeyString, String text) throws Exception {
    PKCS8EncodedKeySpec pkcs8EncodedKeySpec5 = new PKCS8EncodedKeySpec(
        Base64.decodeBase64(privateKeyString));
    KeyFactory keyFactory = KeyFactory.getInstance("RSA");
    PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec5);
    Cipher cipher = Cipher.getInstance("RSA");
    cipher.init(Cipher.DECRYPT_MODE, privateKey);
    byte[] result = cipher.doFinal(Base64.decodeBase64(text));
    return new String(result);
  }

  /**
   * 公钥加密
   *
   * @param publicKeyString 公钥
   * @param text            待加密的文本
   * @return 加密后的文本
   */
  public static String encryptByPublicKey(String publicKeyString, String text) throws Exception {
    X509EncodedKeySpec x509EncodedKeySpec2 = new X509EncodedKeySpec(
        Base64.decodeBase64(publicKeyString));
    KeyFactory keyFactory = KeyFactory.getInstance("RSA");
    PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec2);
    Cipher cipher = Cipher.getInstance("RSA");
    cipher.init(Cipher.ENCRYPT_MODE, publicKey);
    byte[] result = cipher.doFinal(text.getBytes());
    return Base64.encodeBase64String(result);
  }

  /**
   * 构建RSA密钥对
   *
   * @return 生成后的公私钥信息
   */
  public static RsaKeyPair generateKeyPair() throws NoSuchAlgorithmException {
    KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
    keyPairGenerator.initialize(1024);
    KeyPair keyPair = keyPairGenerator.generateKeyPair();
    RSAPublicKey rsaPublicKey = (RSAPublicKey) keyPair.getPublic();
    RSAPrivateKey rsaPrivateKey = (RSAPrivateKey) keyPair.getPrivate();
    String publicKeyString = Base64.encodeBase64String(rsaPublicKey.getEncoded());
    String privateKeyString = Base64.encodeBase64String(rsaPrivateKey.getEncoded());
    return new RsaKeyPair(publicKeyString, privateKeyString);
  }

  /**
   * RSA密钥对对象
   */
  public static class RsaKeyPair {

    private final String publicKey;
    private final String privateKey;

    public RsaKeyPair(String publicKey, String privateKey) {
      this.publicKey = publicKey;
      this.privateKey = privateKey;
    }

    public String getPublicKey() {
      return publicKey;
    }

    public String getPrivateKey() {
      return privateKey;
    }
  }

  public static void main(String[] args) throws Exception {
    String userName = "admin";
    String password = "admin123";
    System.out.println("加密后的用户名: ");
    String userNameEncode = encryptByPublicKey(publicKey, userName);
    System.out.println("加密后的密码: ");
    System.out.println(userNameEncode);
    String passwordEncode = encryptByPublicKey(publicKey, password);
    System.out.println(passwordEncode);

    System.out.println("解密后的用户名: ");
    System.out.println(decryptByPrivateKey(userNameEncode));
    System.out.println("解密后的密码: ");
    System.out.println(decryptByPrivateKey(passwordEncode));
  }

}